[b1gblue]

Hello,

Feeling blonde, but maybe this will help someone else.

I found myself getting a persistent "Script Failed" message when trying to sign in to the YouTube add-on.
Learned how to get a debug log. Put it up on XBMCLogs and was about to post it here. But I didn't...

Before that I'd uninstalled most add-ons, leaving only the ones that were there when YouTube last worked with no issue.
Downgraded from 15.2 RC2 down to the stable Helix build with no success.

The add-on would tell me to activate it twice from Youtube's site but the script would fail before I got an acceptance back.

Suspected the possibility that the good folk at Google are screwing around as my native Youtube apps on my phone and tablet have been intermittently wonky too.

My other Kodi add-ons work fine.

Then I went through the log and it curiously said "User not logged in"

All other Google apps worked fine on my phone and tablet - it was only the YouTube app that was wonky.
Youtube would play perfectly in a browser.

Tried to sign out of my Google account but couldn't from my tablet, so manually synced my Google account.
It was like some kind of sorcery - everything works now.